Apparatus and method for the detection of the body position while sleeping

Abstract

The invention relates to a method and an apparatus for the detection of the body position, especially while sleeping. More particularly, the invention relates to how the main body positions during sleep can be derived from the distribution of the reflection of a projected IR light from a subject's body under a blanket. Additionally, the breathing signals can be analyzed to determine the body posture.

1 . A method for the detection of the posture of a body, especially while sleeping, the method comprising the steps of:
 providing a bedding;   projection of a pattern of electromagnetic radiation at least on a part of said bedding;   detection of the reflection of the projected pattern caused by a body on said bedding;   comparing the reflection pattern with a reflection pattern representing typical body postures.   
     
     
         2 . The method according to  claim 1 , wherein during the comparison of the reflected pattern with a pattern representing typical body postures the subject's body is virtually segmented into at least two major parts: Upper body left and right, middle part left and right, bottom part left and right, of which the sum of the present intensity is computed. 
     
     
         3 . The method according to  claim 1 , wherein the light source for the projection of the pattern of electromagnetic radiation is an IR-LED laser. 
     
     
         4 . The method according to  claim 1 , wherein the projection of the pattern of electromagnetic radiation on said bedding is performed in an intermitted and/or modulated way. 
     
     
         5 . The method according to  claim 1 , wherein the detection of the reflection of the pattern of electromagnetic radiation is a low resolution sensor array. 
     
     
         6 . The method according to  claim 1 , wherein additional information are considered for the determination of the body posture. 
     
     
         7 . The method according to  claim 6 , wherein acoustical information and/or information on the breathing amplitude are used for the determination of the body posture. 
     
     
         8 . The method according to  claim 7 , wherein the breathing characteristics are extracted from a video signal to enhance the detection of the body posture. 
     
     
         9 . The method according to  claim 6 , wherein acoustical information is retrieved via at least two microphones positioned on both sides of the bedding. 
     
     
         10 . The method according to  claim 9 , wherein the orientation of the light source for the pattern projection as well as of the sensor/camera for the determination of the reflection is used when detecting the body posture by deriving heuristics for the main orientations of the sensor/camera and the light source with regard to the bedding. 
     
     
         11 . The method according to  claim 10 , wherein movement information, which is available due to simultaneous actigraphy processing, is used to render a more robust detection due to indications for position changes and relocation of grid segments on the subject's body. 
     
     
         12 . An apparatus for the detection of postures of a body on a bedding, the apparatus comprising:
 A projector for the projection of pattern of electromagnetic waves on said bedding;   A detector for the detection of reflection of the pattern projected by said projector;   A data processing means connected to the detector, said data processing means being capable to compare actual reflection detected by the detector with stored reflection patterns representing typical body postures.   
     
     
         13 . The apparatus according to  claim 12 , further comprising at least one microphone connected to said data processing means. 
     
     
         14 . The apparatus according to  claim 12 , wherein the projector is an IR-LED-laser. 
     
     
         15 . Use of a method according to  claim 11  for the detection of physical health conditions related to the body posture during sleep, or for controlling the environmental situation in or around a bedding in dependence of the body posture.